So, let's say you have a frontend running in your browser at `http://localhost:8080`, and its JavaScript is trying to communicate with a backend running at `http://localhost` (because we don't specify a port, the browser will assume the default port `80`).

digamos que você tenha um frontend rodando no seu navegador em `http://localhost:8080`, e seu JavaScript esteja tentando se comunicar com um backend rodando em `http://localhost` (como não especificamos uma porta, o navegador assumirá a porta padrão `80`).

Portanto, o navegador enviará uma requisição HTTP `OPTIONS` ao backend `:80`, e se o backend enviar os cabeçalhos apropriados autorizando a comunicação a partir dessa origem diferente (`http://localhost:8080`), então o navegador `:8080`...

        isDaemon = true
        uncaughtExceptionHandler = loggingUncaughtExceptionHandler
      }
    }

  private val backend = TaskRunner.RealBackend(threadFactory)
  private val taskRunner = TaskRunner(backend)
  private val queue = taskRunner.newQueue()

  @AfterEach fun tearDown() {
    backend.shutdown()
  }

  @Test fun test() {
    val t1 = System.nanoTime() / 1e6

Browser unter `http://localhost:8080` läuft, und dessen JavaScript versucht, mit einem Backend zu kommunizieren, das unter `http://localhost` läuft (da wir keinen Port angegeben haben, geht der Browser vom Default-Port `80` aus).

Dann wird der Browser ein HTTP-`OPTIONS`-<abbr title="Request – Anfrage: Daten, die der Client zum Server sendet">Request</abbr> an das `:80`-Backend senden, und wenn das Backend die entsprechenden Header sendet, die die Kommunikation von diesem anderen Origin (`...

		// Init and run test on ErasureSD backend with signature v4.
		{serverType: "ErasureSD", signer: signerV4},
		// Init and run test on ErasureSD backend, with tls enabled.
		{serverType: "ErasureSD", signer: signerV4, secure: true},
		// Init and run test on Erasure backend.
		{serverType: "Erasure", signer: signerV4},
		// Init and run test on ErasureSet backend.
		{serverType: "ErasureSet", signer: signerV4},
	}

	ErrUnsupportedBackend = newErrFn(
		"Unable to write to the backend",
		"Please ensure your drive supports O_DIRECT",
		"",
	)

	ErrUnableToWriteInBackend = newErrFn(
		"Unable to write to the backend",
		"Please ensure MinIO binary has write permissions for the backend",
		`Verify if MinIO binary is running as the same user who has write permissions for the backend`,
	)

	ErrPortAlreadyInUse = newErrFn(

* Migrations **Alembic**.
* **CORS** (partage des ressources entre origines multiples, ou *Cross Origin Resource Sharing*).
* *Worker* **Celery** pouvant importer et utiliser les modèles et le code du reste du backend.

* **Alembic** migration.
* **CORS** (Cross Origin Resource Sharing).
* **Celery** worker'ları ile backend içerisinden seçilen işleri çalıştırabilirsiniz.

	clusterDriveMetrics, err := c.clusterDriveMetrics.Get()
	if err != nil {
		metricsLogIf(ctx, err)
	} else {
		m.Set(configStandardParity, float64(clusterDriveMetrics.storageInfo.Backend.StandardSCParity))
		m.Set(configRRSParity, float64(clusterDriveMetrics.storageInfo.Backend.RRSCParity))
	}

	return nil

}

func TestErasureDeleteObjectDiskNotFound(t *testing.T) {
	ctx, cancel := context.WithCancel(t.Context())
	defer cancel()

	// Create an instance of xl backend.
	obj, fsDirs, err := prepareErasure16(ctx)
	if err != nil {
		t.Fatal(err)
	}
	// Cleanup backend directories
	defer obj.Shutdown(t.Context())
	defer removeRoots(fsDirs)

	z := obj.(*erasureServerPools)
	xl := z.serverPools[0].sets[0]